Easily, we can see that there is a successful model that enables humans to prioritize evidence, without looking at all possible evidence. (Science is that model, Science is something that permits this everyday; Scientific hypothesis and Scientific theory both concern evidence prioritization contrary to the concept of belief.)

So, non-beliefism is simply a way to underline what is already possible, scientific thinking. (By clearly identifying a popular and not typically scrutinized paradigm, i.e. belief, and showing why belief contrasts scientific thinking)

In fact, for example, equations don't suddenly work in practice because scientists choose to believe in them; if that were the case, whether or not equations actually followed evidence, scientists could simply supply belief towards whatever notation they came up with, without the need to concern evidence!

Instead, regardless of how much belief or passion we may want to pour into our work, being keen on evidence is thus far the best method mankind has engineered, and evidence prioritization is what has demonstrably enabled us to make progress, and what shall reasonably enable continued progress!

Conclusively, non-beliefism, emphasizes that one may rank his/her presentations as incomplete or temporary expressions (susceptible to future analysis/correction), where one shall aim to hold those expressions especially given evidence, rather than believe, i.e. typically accept them especially absent evidence.

Both incomplete expressions (via non-beliefism) and beliefs are updatable, however belief generally facilitates that mistakes go on unrepaired, by general evidence ignorance, while non-beliefism emphasizes that the individual prioritizes evidence (Rather than especially ignore as seen generally in belief.)